摘要
背景:帕金森病是一种特征为多巴胺能神经元进行性丢失的多因素神经系统疾病,富马酸二甲酯(dimethyl fumarate,DMF)在神经退行性疾病中具有强大的神经保护和免疫调节作用。目的:探究DMF对MPTP诱导的帕金森病小鼠模型的神经保护机制。方法:选取24只C57BL/6系小鼠,随机将其分为对照组、模型组及DMF低剂量和DMF高剂量组。除对照组外,其余各组小鼠腹腔注射MPTP 30 mg/kg,1次/d,连续注射5 d,建立帕金森病的动物模型。每次注射MPTP后间隔30 min给予小鼠灌胃,DMF低剂量组和DMF高剂量组每天分别灌胃DMF 30,50 mg/kg,1次/d,对照组和模型组灌同等剂量的生理盐水,连续灌胃7 d。通过行为学检测、Western Blot、氧化应激标志物检测和免疫组织化学染色等方法,分析DMF对MPTP诱导的帕金森病小鼠氧化应激和Keap1/Nrf2信号通路的调节作用,以及DMF对多巴胺神经元变性的保护机制。结果与结论:①与模型组比较,DMF低剂量组小鼠的运动迟缓和姿势平衡障碍得到明显改善(P<0.01),在DMF高剂量组中的改善更为显著(P<0.01)。②与对照组相比,模型组氧化应激标志物丙二醛明显升高,超氧化物歧化酶表达降低(P<0.01);与模型组相比,DMF低、高剂量组降低了丙二醛的产生,增加了超氧化物歧化酶的表达(P<0.01)。③模型组小鼠的中脑黑质多巴胺能神经元数目和酪氨酸羟化酶蛋白表达较对照组明显减少(P<0.01),而DMF低剂量组小鼠的黑质多巴胺能神经元数目和蛋白表达增多(P<0.01),DMF高剂量组改善更明显(P<0.01)。④模型组Keap1蛋白表达升高伴随Nrf2蛋白表达降低;与模型组相比,DMF组降低了Keap1蛋白表达且伴随Nrf2蛋白表达增多(P<0.01)。⑤结果说明,DMF对帕金森病小鼠黑质区Keap1/Nrf2通路有调控作用,且与剂量呈现正相关(P<0.01),推测DMF依赖于Keap1/Nrf2信号发挥神经元保护作用。
BACKGROUND:Parkinson’s disease is a multifactorial neurological disorder characterized by progressive loss of dopaminergic neurons,and dimethyl fumarate(DMF)has potent neuroprotective and immunomodulatory effects in neurodegenerative diseases.OBJECTIVE:To explore the neuroprotective mechanism of DMF in a mouse model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced Parkinson’s disease.METHODS:Twenty-four C57BL/6 mice were selected and randomly divided into control group,model group,low-dose DMF,and high-dose DMF groups.An animal model of Parkinson’s disease was established in the latter three groups by intraperitoneal injection of 30 mg/kg MPTP,once a day for 5 consecutive days.Intragastric administration was given 30 minutes after each injection of MPTP.Mice in the low-dose DMF group(30 mg/kg)and high-dose DMF group(50 mg/kg)were intragastrically administered once a day for 7 consecutive days.The control and model groups were initially administered the same dose of normal saline.Behavioral testing,western blot,oxidative stress marker detection,and immunohistochemical staining were used to analyze the regulatory effects of DMF on oxidative stress and Keap1/Nrf2 signaling pathway in MPTP-induced Parkinson’s disease mice,as well as the protective mechanism of DMF on degeneration of dopamine neurons.RESULTS AND CONCLUSION:Compared with the model group,mice in the low-dose DMF group exhibited significant improvements in motor retardation and postural imbalance(P<0.01),with even more remarkable improvements observed in the high-dose DMF group(P<0.01).Compared with the control group,the model group showed a significant increase in the oxidative stress marker malondialdehyde and a decrease in superoxide dismutase expression(P<0.01).Compared with the model group,the low-dose DMF group reduced malondialdehyde production and increased superoxide dismutase expression(P<0.01),and similar improvements were observed in the high-dose DMF group(P<0.01).Immunohistochemical and western blot assays demonstrated a significant decrease in the number of dopaminergic neurons and tyrosine hydroxylase protein expression in the substantia nigra of mice in the model group compared with the control group(P<0.01).However,in the low-dose DMF group,there was an increase in the number of dopaminergic neurons and tyrosine hydroxylase protein expression in the substantia nigra(P<0.01),with even more significant improvements in the high-dose DMF group(P<0.01).Western blot results revealed that the model group exhibited elevated Keap1 protein expression and decreased Nrf2 protein expression.In contrast,the DMF groups showed reduced Keap1 protein expression and increased Nrf2 protein expression compared to the model group(P<0.01).To conclude,DMF regulates the Keap1/Nrf2 pathway in the substantia nigra of mice with Parkinson’s disease,and this regulatory effect is positively correlated with the dose of DMF(P<0.01).Therefore,we infer that DMF exerts neuroprotective effects through the Keap1/Nrf2 signaling pathway.
作者
逯冉冉
周旭
张利杰
杨新玲
Lu Ranran;Zhou Xu;Zhang Lijie;Yang Xinling(The Second Affiliated Hospital of Xinjiang Medical University,Urumqi 830028,Xinjiang Uygur Autonomous Region,China;Xinjiang Production and Construction Corps Hospital,Urumqi 830000,Xinjiang Uygur Autonomous Region,China;Xinjiang Medical University,Urumqi 830054,Xinjiang Uygur Autonomous Region,China)
出处
《中国组织工程研究》
CAS
北大核心
2025年第5期989-994,共6页
Chinese Journal of Tissue Engineering Research
基金
国家自然科学基金项目(82160232),项目负责人:杨新玲
新疆维吾尔自治区研究生研究创新基金资助项目(XJ2023G177),项目负责人:逯冉冉。
作者简介
第一作者:逯冉冉,女,1991年生,山东省潍坊市人,汉族,新疆医科大学在读博士,医师,主要从事神经退行性疾病的研究,尤其是帕金森病的研究,https://orcid.org/0009-0002-6891-6966;通讯作者:杨新玲,博士,主任医师,博士生导师,新疆医科大学第二附属医院,新疆维吾尔自治区乌鲁木齐市830028,新疆医科大学,新疆维吾尔自治区乌鲁木齐市830054。
